Spectroscopic study of doped strontium ruthenates compositions

Extraordinary properties of Sr₂RuO₄ have attracted much attention since the discovery of superconductivity in this material in [Y. Maeno et.al., Nature 372, 532 (1994)]. This material are isostructural to the high T_c cuprate superconductors which motivated extensive search of physically and chemically modified ruthenates [Gulian, et.al., Quantum Stud. Math. Found., 5, 161 (2018)]. One of the compositions Sr₂Ru_1-xRe_xO₃Se, revealed feature, which most naturally fitted into the pattern of presence of a small fraction of superconducting phase in a multiphase sample with the dominant ferromagnetic phase, almost masking out this superconductivity at ~30 K. We present compositional, morphological, structural, magnetotransport, heat capacity, magnetic susceptibility, Raman and terahertz spectroscopy data to facilitate theoretical analysis of metamagnetism vs. superconductivity in this material.